Phase 1 is part of a 15-mile corridor improvement project to improve safety and reliability and reduce congestion along I-90 from Hyak to the Easton vicinity.

On an average day, 28,000 vehicles travel over Snoqualmie Pass and it doubles on weekends and holidays. Traffic volumes are expected to increase 2.1 percent every year, reaching an average of over 41,000 vehicles per day by 2030.

Currently, WSDOT is improving the first five miles of the project from Hyak to Keechelus Dam.

The End Result

WSDOT will increase capacity and improve safety by:

Adding a new lane in each direction

Replacing deteriorating concrete pavement

Reducing road closures due to avalanches

Adding and replacing bridges and culverts

Straightening sharp curves

Stabilizing rock slopes

Project Benefits

Safety. Corrective measures will reduce the risk of avalanche and associated road closures within the project area as well as reduce the risk of rock and debris slides from unstable slopes onto the roadway.

Congestion Relief. WSDOT will increase capacity by 50 percent in each direction to accommodate projected traffic volumes for the next 20 years. Crews will extend chain-up-and-off areas assisting freight vehicles.

Environment. WSDOT will reduce the risk of collisions between wildlife and vehicles by building wildlife crossings.

What is the project timeline?

Spring 2009 - construction begins

Fall 2018 - construction complete

Financial Information

The 2005 gas tax invested $551 million in the I-90 corridor.

This project recently had construction change orders of more than $500,000. View all change orders.